Traditionally, the injection method of liquid crystal during manufacturing a liquid crystal panel is to slowly inject liquid crystal into a space between two combined glass substrates according to the capillarity principle, but the disadvantage is that the method consumes much time and waste material of liquid crystal
The foregoing injection method of liquid crystal is gradually replaced by a one-drop filling (ODF) technology. In the one-drop filling technology, liquid crystal is firstly and directly dropped onto a glass substrate through a liquid crystal dropping device, and then the glass substrate is aligned and combined with the other glass substrate. This new technology can substantially save filling time of liquid crystal and material of liquid crystal.
However, when manufacturing some liquid crystal panel having liquid crystal alignment capable of improving visual angles, the liquid crystal is dropped onto an alignment film of a substrate by the one-drop filling technology, wherein the alignment film is impacted by the drops of liquid crystal to thus cause the phenomenon of drop Mura defect occurred on a finished product.
For more details, referring now to FIG. 1A, a schematic view of a traditional one-drop filling (ODF) technology dropping a liquid crystal composition onto an alignment film of a transparent substrate is illustrated. Referring to FIGS. 1B and 1C, schematic views of reactive monomers 1′ of liquid crystal in the liquid crystal composition deposited on a polyimide surface 2′ of the alignment film are illustrated, wherein the phenomenon of drop Mura defect is caused because different amounts of the reactive monomers 1′ of liquid crystal are unevenly deposited on the polyimide surface 2′ of the alignment film on the transparent substrate.
The reactive monomers 1′ of liquid crystal used by the traditional ODF technology have the following molecular formula (I):

When changing the cell gap of the liquid crystal to be smaller than 3.8 μm, it causes that the traditional reactive monomers of liquid crystal can not be widely dispersed on a large area of the polyimide surface of the alignment film, and thus different amounts of the reactive monomers of liquid crystal are unevenly deposited on the polyimide (PI) surface of the alignment film, as shown in FIG. 1. Thus, when the cell gap of the liquid crystal is smaller than 3.8 μm, there will be the phenomenon of drop Mura defect on the liquid crystal panel.
Referring now to Tab. 1, observed results of the phenomenon of drop Mura defect for of the traditional reactive monomer of liquid crystal under conditions of various cell gaps of liquid crystal are shown in Tab. 1. Apparently, as shown in Tab. 1, when the cell gap of the liquid crystal is smaller than 3.8 μm, there will be the phenomenon of drop Mura defect.
TABLE 1phenomenon ofCell gapreactive monomerdrop Mura defect3.8 μmmolecular formula (I)Few3.5 μmmolecular formula (I)Many3.3 μmmolecular formula (I)Many3.0 μmmolecular formula (I)More
For more details, the reason causing the phenomenon of drop Mura defect is that the interaction between the reactive monomers of liquid crystal and the PI surface of the alignment film is excess, and thus it is disadvantageous to evenly deposit the liquid crystal composition containing the reactive monomers of liquid crystal onto the polyimide surface of the alignment film.
As a result, it is necessary to provide a reactive monomer (RM) of liquid crystal having a modified group to solve the problems existing in the conventional technologies, as described above.